Rolex uses 904L stainless steel for its steel watch cases. 904L is mainly used in the high technology, aerospace and chemical industries, where maximum resistance to corrosion is essential. A superalloy, 904L is extremely resistant and highly polishable. It maintains its beauty even in the harshest environments.
The black dial of the Sea-Dweller has the large hands and indices reserved for Rolex professional models. The dial bears the name Sea-Dweller in red, a reference to the first model. The innovative Chromalight display on the dial pushes back the boundaries of visibility in dark environments. Its distinctive blue glow lasts up to eight hours with a uniform luminosity, practically twice as long as that of standard luminescent materials.